GLENDALE, AZ – DECEMBER 31: C.J. Fuller #27 of the Clemson Tigers hauls in a touchdown pass over C.J. Saunders #17 of the Ohio State Buckeyes during the second quarter of the 2016 PlayStation Fiesta Bowl at University of Phoenix Stadium on December 31, 2016 in Glendale, Arizona. (Photo by Christian Petersen/Getty Images)Wednesday, former Clemson running back C.J. Fuller, who was a key part of the team’s national championship squad in 2016, passed away unexpectedly. Details surrounding his death have been hard to come by.Thursday, in an interview with The Greenville News, Fuller’s aunt Zola Fuller provided a bit of information regarding her nephew’s death. She says he was doing physical therapy for his knee when he started to experience chest pains.Fuller also said the former Clemson running back had been experiencing chest pains earlier in the day. She says the family thinks his death had something to do with a blood clot.Here’s more:“He had been having some chest pains before that day, but they got worse fast,” she said she was told by her siblings at the hospital with Fuller. “He was conscious at one point, but when he got to the hospital, his speech was slurred. Before we knew it, he was gone.“We think it had something to do with a blood clot, but you just don’t expect someone his age to be gone so fast.”Fuller transferred from the school for his final year of eligibility, but he got his degree in August.Fuller played three seasons at Clemson. His best year was 2017, in which he gained 217 yards on 58 carries with three touchdowns. In his team’s College Football Playoff semifinal win over Ohio State in 2016, he scored an integral touchdown.Fuller’s official cause of death won’t be revealed until his autopsy is complete in a few weeks.